Conventional electric guitars interface with a single amplifier, due to the size and expense of an amplifier. Multiple pickups on the guitar are adapted to receive a signal from the vibration of guitar strings. Due to the different location of the pickups, each pickup may interpret a slightly different sound from the same string. A typical guitar has neck, bridge, and middle pickups, referring to the location of the pickup on the instrument. Conventional guitars employ a selector switch or the like on the guitar to direct signals from a particular pickup to the amplifier or receiver connected to the guitar.
Modern electronics allow recordation and mixing of musical audio signals, and widely available applications (apps) allow even a novice user to perform sophisticated manipulations of multiple recorded tracks. These modern apps allow users to perform sound editing on a standard computing device (e.g. laptop or smartphone) to a level which was once only available to professionals having expensive hardware.
Conventional musical instruments, however, typically deliver a single (mono) sound signal. Performed music requires multiple microphones to capture stereo left and right signals. Some instruments, such as electric guitars, directly deliver an electronic medium, however it is still a mono signal.